The invention concerns to a method and devices for the drying of damp material, in particular of damp laundry, according to the generic part of the claim 1 or the claim 13.
The drying of laundry is a problem solved many times by means of different technological facilities. Besides the pure passive drying in the house or at the fresh air at present mainly so-called drum dryers are used for this, into which the laundry to be dried is entered after the stage of washing and is then pressurized with warm air under heating and simultaneous mechanical rotary movement. In these drum dryers the laundry is subject to a great mechanical load at simultaneously high temperatures, by which as a rule the laundry fibers are damaged strongly. Through this it comes to felting of the clothes and shrinking of the laundry pieces, whereby the laundry altogether can get useless. Drying the laundry in drum dryers is therefore problematic and also leads at a proper treatment of the laundry in the drum dryer at a frequent repetition to the reduction of the laundry quality.
Furthermore it is known for example from DE 42 35 560 C2 to arrange a drying cabinet so that inside hanging laundry can be dried by means of a warm air blast in a gentle way and without mechanical load. The laundry pieces are brought in in hanging order and dried by warm air supplied from the outside in such a drying cabinet. By this the mechanical load of laundry is reduced to zero when drying, though an operation of such a drying cabinet is only possible, if the warm air, escaping from the drying cabinet and provided with high humidity, is lead to the output air guide to the open.
It is therefore known from DE 36 32 820 C2 to equip such a drying cabinet with a condenser, which cools down the air circulating in the closed circulation within the drying cabinet so much that the humidity condenses and can be led away into corresponding on-catch container. Through this a drying is made possible also without a corresponding removal of humid air, also the required energy quantity is smaller for heating the drying cabinet. Though the laundry will keep the crinkle remained after hanging up or the existing creases during this drying process, so that laundry taken dryly from the drying cabinet must than still be ironed. A part of the possible rationalization of the housework obtained by using the drying cabinet is given away.
It is therefore the object of the present invention to develop a drying cabinet or a method for drying in such a manner, that the laundry is dried if possible without afterwards necessary ironing and an operation of the drying cabinet is also possible without an additional output air guide.
The solution of the object according to the invention corresponding to the method arises from the characterising features of claim 1 in interaction with the features of the pre-characterising part. Further advantageous developments of the invention arise from the dependent claims.
The invention starts out from a method for the drying of a damp material, in particular of a damp laundry, whereby the material is treated in a treatment chamber of a drying cabinet in mechanically immobile condition in which air is directed through the treatment chamber and over a condenser, which is cooled by an outer air circuit, and the moisture contained in the air condenses on the condenser and can be led away. This generic method is developed further by the fact that the air is circulated over the still damp material for drying at least during a period of the drying of the material with a switched-off condenser in a closed loop through the treatment chamber in which the pre-smoothed material at increasing temperature in the treatment chamber is exposed to steam or increased humidity generated at least partly from the dampness of the material or the increased humidity of the air circulating around with a temperature up to between 90 degrees Celsius and 125 degrees Celsius and is relaxed. and smoothed by the steam or the increased humidity in relation to creases, folds or similar from preceding treatments. By this with an increasing dehumidify of the residual humidity of the air after the beginning of the condensation at the condenser the material is freed of creases, folds or the like and is dried without ironing. The treatment of the material works as in the case of a steam shower by means of tension release of the fibres of the material by which creases, folds or the like form themselves gradually back as in the case of a steam shock of an iron and the material is thus then dried in a smooch state. Therefore a separate ironing treatment after drying gets superfluous, a great time-saving is attainable through that. By the production of the steam or the increased humidity from the dampness out of the material itself when brought in the advantage is obtained that this humidity is already withdrawn from the material and hereby a drying of the material walks along. Therefore in the phase of on-heating of the treatment chamber essentially only the charging of the treatment chamber with heat is necessary, the charging with steam from an external source must not be carried out. A particularly good relationship of removal of creasing regions and folds related to the drying time can be obtained, if the maximum temperature of air and/or steam or increased humidity during the phase of the transition of the steam or the increased humidity over the material inside the treatment chamber amounts between 90 and 125 degrees Celsius.
A first advantageous arrangement of the method provides that during the formation of the steam or the increased humidity the temperature is increased in the treatment chamber. Through this the steam or the increased humidity is won from the residual dampness of the material by evaporating or vaporizing the residual dampness and changing it into the air circulating in the treatment chamber. The circulating air can contain different quantities of humidity or of steam in dependence of the temperature so that at the rise of the temperature a considerable quota of the rest dampness of the material already changes into the circulating air. The drying effect of the material walking along with this at simultaneous generation of the steam needed for the elimination of creases and folds increases the economic efficiency of the method by reduction of the energy costs.
Another advantageous arrangements of the method provides that the condensation starts after a time delay after the beginning of the drying and the generation of the steam or the increased humidity. By this fact it can be obtained that just at the beginning of the drying a volume steam made replete with very much steam or increased humidity circulates through the treatment chamber which reliably removes the creases and folds of the material.
It is particularly advantageous if the change-over from the transition of the steam or the increased humidity over the material in the closed circulation to the phase of the increasing withdrawal of the air humidity from the treatment chamber by means of condensation at the condenser is carried out slidingly. By this a particularly gentle treatment of the material in the treatment chamber for a safe removal of the creases and folds can be combined with a drying phase starting gently, which allows a safe removal of the creases and folds at a simultaneously good and gentle drying of the material.
Furthermore it is conceivable that the steam or the increased humidity is at least partly supplied also from an external source to the treatment chamber. By this additional steam or a larger quantity of steam can be supplied to the material in shorter time by means of the external source without the production of steam or increased humidity being able to lead to a damage done to the material in the inner of the treatment chamber due to a high temperature supply.
Another improvement in the use of a drying cabinet according to invention can be obtained if after the phase of the transition of the steam or the increased humidity and at or after the drying the material is exposed in the same treatment chamber in an open circulation under influence of external air supplied from the outside to a further treatment like a further drying, a disinfection, a sterilization, a pollutant removal or the like. By this in the same treatment chamber the drying treatment with the obtainment of a non-iron drying of the material can be with further perhaps necessary steps of the treatment of the material as well as disinfecting the material in hospitals or perhaps a removal of pollutants at production fresh objects for example. For such combination treatments the material then doesn""t have to be reloaded any more from the treatment chamber into another device but can remain in the treatment chamber and be given further treatment there directly. The treatment in the open circulation is always necessary if e.g. volutile constituents shall be removed from the material or a process sequence in the closed circulation would cause two great loads of the material.
By the addmix of external air into the treatment chamber the temperature can be reduced in the treatment chamber so that in addition to the possible further treatment of the material in the open circulation a shorter cooling from the drying phase is also attainable.
Furthermore the invention describes a drying cabinet for the execution of the method according to claim 1. which shows a treatment chamber lockable relative to the surrounding by which air with steam or increased humidity can be guided in a closed circulation and over a condenser and the humidity contained in the air condenses at the condenser and can be carried away into an on-catch container whereby the condenser can be cooled by a cooling stream of air which is drawn in from the external air.
Furthermore it can be provided that the cooling steam of air can be guided between the outside wall of the treatment chamber and the outside wall of the drying cabinet for cooling the outside wall of the drying cabinet against thermal pollutions coming from the treatment chamber.
The air with steam or increased humidity guided in the closed circulation through the treatment chamber and over the condenser can also be injectable in the form of colliding air steams into the treatment chamber by means of lateral opening arranged in opposite walls of the treatment chamber and can be deductible from the treatment chamber again sub-sided of the treatment chamber. By this a material mixture of the inside of the treatment chamber is obtainable which leads to a high absorption of the dampness of the material by the air.
Furthermore the invention describes a drying cabinet for the drying of a damp material, in particular. of a clamp laundry, for the execution of the method according to claim 1 in which the material is treated in a treatment chamber in mechanically immobile condition in which air is led in a closed circulation through the treatment chamber and over a condenser and the humidity contained in the air condenses at the condenser and can be led away. Such a drying cabinet shows flaps at the drying cabinet to be switched related to the operation of the drying cabinet between the circulation in the closed circulation and a treatment in the open circulation which make possible an introduction and exhausting of external air to or from the treatment chamber. In a further development the flaps can open and close time and/or temperature controlled and/or state dependent of the drying state of the material. Such an arrangement of the drying cabinet makes possible a combined and automated operation mode both in the closed circulation and in the open circulation and offers therefore different usage possibilities of the same device. So it can be avoided, that for example for the disinfection or sterilization a separate device must be bought since a disinfection or sterilization normally takes place in the open circulation, but the drying according to the invention in the closed circulation.